Role of secondary structure in protein-phospholipid surface interactions: reconstitution and denaturation of apolipoprotein C-I:DMPC complexes.

ABSTRACT: Binding of protein to a phospholipid surface is commonly mediated by amphipathic alpha-helices. To understand the role of alpha-helical structure in protein-lipid interactions, we used discoidal lipoproteins reconstituted from dimyristoylphosphatidylcholine (DMPC) and human apolipoprotein C-I (apoC-I, 6 kDa) or its mutants containing single Pro substitutions along the sequence and differing in their alpha-helical content in solution (0-48%) and on DMPC (40-75%). Thermal denaturation revealed that lipoprotein stability correlates weakly with the protein helix content: proteins with higher alpha-helical content on DMPC may form more stable complexes. Lipoprotein reconstitution upon cooling from the heat-denatured state and DMPC clearance studies revealed that protein secondary structure in s

SUBMITTER: Benjwal S 

PROVIDER: S-EPMC2584444 | biostudies-literature | 2007 Apr

REPOSITORIES: biostudies-literature